A simulation method and system for airflow control of a high-frequency solenoid valve

Abstract

This invention discloses a simulation method and system for airflow control of a high-frequency solenoid valve. The method includes: establishing a magnetic field simulation model based on the components of the high-frequency solenoid valve; establishing an airflow field simulation model based on the internal structure of the high-frequency solenoid valve; establishing a coupled simulation model of the solenoid valve based on the magnetic field simulation model, the airflow field simulation model, and the electromagnetic force and air pressure on the armature; and simulating the response time of the high-frequency solenoid valve based on the coupled simulation model to complete the airflow control simulation of the high-frequency solenoid valve. This method, based on Maxwell's electromagnetic field theory and fluid dynamics, establishes a multi-physics coupled simulation model, simulates and analyzes the dynamic changes in armature displacement response characteristics and outlet pressure, and explores the airflow control characteristics and response time of the high-frequency solenoid valve. This effectively reduces the testing work for the response characteristics of the high-frequency solenoid valve, saves experimental costs, and provides a theoretical basis for the design of high-frequency solenoid valves in intelligent ore sorting machines.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic valve airflow control technology, specifically relating to a high-frequency electromagnetic valve airflow control simulation method and system. Background Technology

[0002] High-frequency solenoid valves are key to the precise ore separation function of intelligent ore separators. The intelligent ore separator achieves timed ore separation by controlling the high-speed switching of the high-frequency solenoid valves' open and closed states.

[0003] However, because electromagnetic force cannot change instantaneously, high-frequency solenoid valves exhibit opening and closing delays. If the opening delay is too long, the ore cannot be purged at the predetermined time, preventing it from falling to the intended position. If the closing delay is too long, it may interfere with the subsequent ore purging effect. If the response speed of the high-frequency solenoid valve is too slow, it cannot meet the high-frequency operating requirements of the intelligent ore sorting machine, thus reducing its efficiency.

[0004] Therefore, how to accurately analyze the opening, closing, and response time of high-frequency solenoid valves in order to improve the airflow control accuracy of high-frequency solenoid valves has become an urgent problem to be solved. Summary of the Invention

[0005] In view of the shortcomings of the prior art, one of the objectives of this invention is to provide a high-frequency solenoid valve airflow control simulation method to accurately analyze the opening, closing and response time of the high-frequency solenoid valve, so as to improve the airflow control accuracy of the high-frequency solenoid valve.

[0006] The second objective of this invention is to provide a system for implementing the high-frequency solenoid valve airflow control simulation method.

[0007] This invention provides a high-frequency solenoid valve airflow control simulation method, comprising the following steps:

[0008] S1. Based on the components of a high-frequency solenoid valve, establish a magnetic field simulation model;

[0009] S2. Based on the internal structure of the high-frequency solenoid valve, establish an airflow field simulation model;

[0010] S3. Based on the magnetic field simulation model, the airflow field simulation model, and the electromagnetic force and air pressure on the armature, establish a electromagnetic valve coupling simulation model;

[0011] S4. Based on the electromagnetic valve coupling simulation model, simulate the displacement response data of the armature and the valve port pressure response data of the high-frequency electromagnetic valve to obtain the response time of the high-frequency electromagnetic valve and complete the airflow control simulation of the high-frequency electromagnetic valve.

[0012] Step S1 includes the following steps:

[0013] A mathematical model of the magnetic field is established based on Maxwell's equations.

[0014] A magnetic field geometric model is established based on the dimensions and materials of the components of the high-frequency solenoid valve.

[0015] Based on the aforementioned magnetic field mathematical model and the aforementioned magnetic field geometric model, a magnetic field simulation model is determined;

[0016] A first boundary condition is set, which includes an excitation current curve; an excitation is applied to the magnetic field simulation model based on the excitation current curve to simulate the electromagnetic force on the armature.

[0017] The aforementioned mathematical model of the magnetic field, based on Maxwell's equations, is as follows:

[0018] The magnetic field can be solved based on Maxwell's electromagnetic valve theory. The differential form of Maxwell's equations is as follows:

[0019]

[0020] The auxiliary equations between the four field quantities in the above formula are:

[0021]

[0022] Where H represents magnetic field strength; J represents current density; D represents electric displacement vector; E represents electric field strength; and B represents magnetic flux density. Indicates charge density; Indicates the permeability of soft magnetic materials; Indicates the dielectric constant; This indicates the electrical conductivity of soft magnetic materials.

[0023] Introducing the vector magnetic potential A, we have:

[0024]

[0025] After solving for the above field quantities using the finite element method, the electromagnetic force on the armature is solved using Maxwell's stress tensor method, and the formula for the mathematical model of the magnetic field is obtained as follows:

[0026]

[0027] in, This indicates the electromagnetic force acting on the armature; Permeability in vacuum S represents any closed surface of the medium; n represents the unit normal vector on that closed surface.

[0028] The step of establishing a magnetic field geometric model based on the dimensions and materials of the components of the high-frequency solenoid valve includes: setting an air threshold as a magnetically insulating boundary outside the high-frequency solenoid valve; setting material characteristic parameters for each component and the air threshold; and modeling the components of the high-frequency solenoid valve and the air threshold based on the dimensions of each component and the material characteristic parameters to establish the magnetic field geometric model.

[0029] The magnetic field mathematical model and the magnetic field geometric model together constitute the magnetic field simulation model. After the magnetic field simulation model is established, the first boundary condition is set. A cube-shaped air domain is set outside the magnetic field simulation model as the computational domain to isolate the influence of the external magnetic field and at the same time make the magnetic field boundary condition meet the requirements of infinite far field. The magnetic field is excited by an external current through a coil.

[0030] After applying an excitation current to the magnetic field based on the first boundary condition, the internal magnetic field of the solenoid valve is obtained through simulation.

[0031] Simulate the electromagnetic force experienced by the armature.

[0032] In step S2, based on the internal structure of the high-frequency solenoid valve, an airflow field simulation model is established to simulate the air pressure on the armature. This includes: extracting the airflow domain of the high-frequency solenoid valve based on its internal structure; establishing the airflow field simulation model based on the airflow domain of the high-frequency solenoid valve; simulating the airflow field in the airflow field simulation model using a turbulence model; setting a second boundary condition, which includes any one or more of inlet boundary parameters, outlet boundary parameters, and turbulence model setting parameters; and simulating the air pressure on the armature using control equations based on the second boundary condition, the airflow field simulation model, and the turbulence model, where the control equations include any one or more of the mass conservation equation, momentum conservation equation, and energy conservation equation.

[0033] The step of extracting the airflow domain of the high-frequency solenoid valve based on its internal structure includes: determining the gas inlet, gas flow direction, and gas outlet based on the internal structure of the high-frequency solenoid valve; setting an external flow field based on the gas outlet; and extracting the airflow domain based on the gas inlet, the gas flow direction, and the external flow field.

[0034] Fluid-structure interaction was used to analyze the effect of airflow on armature motion and the pressure response characteristics of airflow.

[0035] The air pressure on the armature is calculated by integrating the air pressure on the upper and lower surfaces of the armature using the following formula:

[0036]

[0037] In the formula, represents the air pressure exerted on the armature; p represents the air pressure exerted on the upper and lower surfaces of the armature; Indicates the surface area of ​​the armature that bears the force; Represents the unit normal vector of the surface;

[0038] Using k- Turbulence model simulates the airflow field inside the solenoid valve;

[0039] Using the arbitrary Lagrange-Euler method, the moving armature structure is defined as the airflow field boundary, and the dynamic changes of the airflow field during the armature movement are simulated using a dynamic mesh.

[0040] For the turbulence model, wall functions are selected for wall treatment, and wall conditions are set as slip boundary conditions.

[0041] Based on the second boundary condition, the airflow field simulation model, and the turbulence model, the air pressure on the armature is simulated through the control equation.

[0042] In step S3, based on the magnetic field simulation model, the airflow field simulation model, and the electromagnetic force and air pressure acting on the armature, a coupled simulation model of the solenoid valve is established to simulate the displacement response data of the armature and the valve orifice pressure response data of the high-frequency solenoid valve. This includes: establishing a dynamic model based on the electromagnetic force and air pressure acting on the armature; establishing the coupled simulation model of the solenoid valve based on the magnetic field simulation model, the airflow field simulation model, and the dynamic model; simulating the coupled simulation model of the solenoid valve using a dynamic mesh; and solving the coupled simulation model of the solenoid valve through transient analysis to simulate the displacement response data of the armature and the valve orifice pressure response data of the high-frequency solenoid valve.

[0043] Add a solid mechanics module to COMSOL, and use the electromagnetic force and air pressure obtained from the above magnetic field and airflow field simulations as inputs to the dynamic model to simulate the armature displacement. In the solid mechanics module, specify the axial displacement of the armature as 0-0.2mm to fix its range of motion. At the same time, transfer the displacement as a variable of the magnetic field and airflow field to the above physical fields to analyze the airflow response characteristics during the armature movement. Through COMSOL's built-in magnetic field model, turbulence model, solid mechanics model, fluid-structure interaction model, and magnetomechanical model, realize the parameter transfer between the various physical fields, and construct an electromagnetic valve coupled simulation model of the electromagnetic field, airflow field, and motion field.

[0044] The step of using a moving mesh to simulate the coupled simulation model of the solenoid valve includes: setting the fluid region in contact with the armature as the deformation domain of the moving mesh, and setting the boundary of the deformation domain as a fixed boundary to determine the moving mesh setting information; and using the moving mesh to simulate the coupled simulation model of the solenoid valve based on the moving mesh setting information.

[0045] The simulation of the solenoid valve coupling simulation model using a dynamic mesh further includes: obtaining the mesh quality parameters of the dynamic mesh during the simulation process; and re-meshing the mesh when the mesh quality parameters are less than the mesh quality threshold.

[0046] The present invention also provides a system for implementing the high-frequency solenoid valve airflow control simulation method, including a magnetic field simulation model construction module, an airflow field simulation model construction module, a solenoid valve coupling simulation model construction module, and a solenoid valve airflow control simulation module;

[0047] The magnetic field simulation model building module establishes a magnetic field simulation model based on the components of the high-frequency solenoid valve and uploads the data to the solenoid valve coupling simulation model building module.

[0048] The airflow field simulation model building module establishes an airflow field simulation model based on the internal structure of the high-frequency solenoid valve and uploads the data to the solenoid valve coupling simulation model building module.

[0049] The electromagnetic valve coupling simulation model building module establishes a electromagnetic valve coupling simulation model based on the received data, the magnetic field simulation model, the airflow field simulation model, and the electromagnetic force and air pressure on the armature, and uploads the data to the electromagnetic valve airflow control simulation module.

[0050] Based on the received data and the electromagnetic valve coupling simulation model, the solenoid valve airflow control simulation module simulates the displacement response data of the armature and the valve port pressure response data of the high-frequency solenoid valve to obtain the response time of the high-frequency solenoid valve and complete the high-frequency solenoid valve airflow control simulation.

[0051] This invention discloses a simulation method and system for airflow control of a high-frequency solenoid valve. Based on Maxwell's electromagnetic field theory and fluid dynamics, the method establishes a multi-physics coupled simulation model of the high-frequency solenoid valve, analyzes the dynamic changes in armature displacement response characteristics and outlet pressure, and explores the airflow control characteristics and response time of the high-frequency solenoid valve. This method effectively reduces the testing work for the response characteristics of high-frequency solenoid valves, saves experimental costs, and provides a theoretical basis for the design of high-frequency solenoid valves in intelligent ore sorting machines. Attached Figure Description

[0052] Figure 1 This is a schematic diagram of the structure of a separation execution system for an intelligent ore sorting machine;

[0053] Figure 2 This is a schematic diagram of the structure of a high-frequency solenoid valve;

[0054] Figure 3 This is a schematic flowchart of the method of the present invention;

[0055] Figure 4 This is a schematic diagram of the system of the present invention;

[0056] Figure 5 A schematic diagram of a magnetic field geometric model provided in an embodiment of this application;

[0057] Figure 6 A schematic diagram of the BH magnetization curve of DT4 provided in an embodiment of this application;

[0058] Figure 7 A schematic diagram of a magnetic field line distribution cloud map provided in an embodiment of this application;

[0059] Figure 8 A schematic diagram of the electromagnetic force variation curve of an armature provided in an embodiment of this application;

[0060] Figure 9 A schematic diagram of an airflow field simulation model provided in an embodiment of this application;

[0061] Figure 10 A schematic diagram of the airflow pressure cloud when a solenoid valve is fully open, provided as an embodiment of this application;

[0062] Figure 11 A schematic diagram of the interaction of multiple physics fields in a high-frequency solenoid valve provided in an embodiment of this application;

[0063] Figure 12 A schematic diagram illustrating the changes in electromagnetic force and pneumatic pressure over time during a switching process of a high-frequency solenoid valve, provided as an embodiment of this application.

[0064] Figure 13 A schematic diagram of the displacement response curve of an armature provided in an embodiment of this application;

[0065] Figure 14 A schematic diagram of the valve orifice pressure response curve of a high-frequency solenoid valve provided in an embodiment of this application; Detailed Implementation

[0066] The intelligent ore sorting machine combines high-precision detection technology and recognition algorithms to achieve efficient ore identification and screening. Ore enters the conveyor belt via a vibrating feeder, where an imaging system captures its appearance features, and recognition algorithms analyze information such as color, shape, and texture. The control system judges the ore quality based on the analysis results and issues commands to the separation execution system, which controls the airflow to separate the ore, achieving efficient automatic sorting. The high-frequency solenoid valve, as the core component of the airflow control in the separation execution system, is crucial for the intelligent ore sorting machine to accurately perform its ore separation function. The structure of the intelligent ore sorting machine's separation execution system is as follows: Figure 1As shown, the high-frequency solenoid valve connects the air blasting gun to the external air supply system. When the solenoid valve opens, high-pressure gas needs to pass through the high-frequency solenoid valve into the blasting plate, where it is sprayed by the air blasting gun to strike the ore. The intelligent ore separator achieves timed ore separation by controlling the high-speed switching of the high-frequency solenoid valve's open / closed state.

[0067] High-frequency solenoid valves utilize the principle of electromagnetism. By applying current to a coil, a magnetic field is generated, which in turn drives an armature to open the valve using electromagnetic force. A high-frequency solenoid valve mainly consists of a coil, an iron core, a moving armature, and a housing. The structure of a high-frequency solenoid valve is as follows: Figure 2 As shown. In the initial state, the solenoid valve coil is not energized, and the armature is pressed tightly against the end cover by air pressure, so the solenoid valve is closed; airflow is cut off. When current is applied to the coil, the armature begins to move under the action of electromagnetic force, the solenoid valve opens, airflow occurs, and high-pressure gas is ejected at high speed through the air exhaust gun to strike the ore, achieving ore separation. When the coil is de-energized, the electromagnetic force gradually decreases, the armature returns to its original position under the action of air pressure, the solenoid valve closes, the airflow is cut off, and the jetting ends. By rapidly switching the high-frequency solenoid valve, the airflow can be precisely controlled to blow the ore at a specified time point to achieve ore separation. However, since the electromagnetic force cannot change instantaneously, the high-frequency solenoid valve exhibits opening and closing delays. If the opening delay of the solenoid valve is too long, it cannot blow the ore at the predetermined time point, causing the ore to fail to fall to the predetermined position; if the closing delay of the solenoid valve is too long, it may interfere with the subsequent ore blowing effect. At the same time, the response speed of the solenoid valve is too slow to meet the high-frequency working requirements of the intelligent ore sorting machine, thus dragging down the working efficiency of the sorting machine.

[0068] This invention provides a simulation method for airflow control of a high-frequency solenoid valve, the flowchart of which is shown below. Figure 3 As shown, it includes the following steps:

[0069] S1. Based on the components of a high-frequency solenoid valve, establish a magnetic field simulation model;

[0070] Step S1 includes the following steps:

[0071] A mathematical model of the magnetic field is established based on Maxwell's equations.

[0072] A magnetic field geometric model is established based on the dimensions and materials of the components of the high-frequency solenoid valve.

[0073] Based on the aforementioned magnetic field mathematical model and the aforementioned magnetic field geometric model, a magnetic field simulation model is determined;

[0074] A first boundary condition is set, which includes an excitation current curve; an excitation is applied to the magnetic field simulation model based on the excitation current curve to simulate the electromagnetic force on the armature.

[0075] The aforementioned mathematical model of the magnetic field, based on Maxwell's equations, is as follows:

[0076] The magnetic field can be solved based on Maxwell's electromagnetic valve theory. The differential form of Maxwell's equations is as follows:

[0077]

[0078] The auxiliary equations between the four field quantities in the above formula are:

[0079]

[0080] Where H represents magnetic field strength; J represents current density; D represents electric displacement vector; E represents electric field strength; and B represents magnetic flux density. Indicates charge density; Indicates the permeability of soft magnetic materials; Indicates the dielectric constant; This indicates the electrical conductivity of soft magnetic materials.

[0081] Introducing the vector magnetic potential A, we have:

[0082]

[0083] After solving for the above field quantities using the finite element method, the electromagnetic force on the armature is solved using Maxwell's stress tensor method, and the formula for the mathematical model of the magnetic field is obtained as follows:

[0084]

[0085] in, This indicates the electromagnetic force acting on the armature; Permeability in vacuum S represents any closed surface of the medium; n represents the unit normal vector on that closed surface.

[0086] The step of establishing a magnetic field geometric model based on the dimensions and materials of the components of the high-frequency solenoid valve includes: setting an air threshold as a magnetically insulating boundary outside the high-frequency solenoid valve; setting material characteristic parameters for each component and the air threshold; and modeling the components of the high-frequency solenoid valve and the air threshold based on the dimensions of each component and the material characteristic parameters to establish the magnetic field geometric model.

[0087] The magnetic field mathematical model and the magnetic field geometric model together constitute the magnetic field simulation model. After the magnetic field simulation model is established, the first boundary condition is set. A cube-shaped air domain is set outside the magnetic field simulation model as the computational domain to isolate the influence of the external magnetic field and at the same time make the magnetic field boundary condition meet the requirements of infinite far field. The magnetic field is excited by an external current through a coil.

[0088] After applying an excitation current to the magnetic field based on the first boundary condition, the internal magnetic field of the solenoid valve is obtained through simulation.

[0089] Simulate the electromagnetic force experienced by the armature.

[0090] S2. Based on the internal structure of the high-frequency solenoid valve, establish an airflow field simulation model;

[0091] In step S2, based on the internal structure of the high-frequency solenoid valve, an airflow field simulation model is established to simulate the air pressure on the armature. This includes: extracting the airflow domain of the high-frequency solenoid valve based on its internal structure; establishing the airflow field simulation model based on the airflow domain of the high-frequency solenoid valve; simulating the airflow field in the airflow field simulation model using a turbulence model; setting a second boundary condition, which includes any one or more of inlet boundary parameters, outlet boundary parameters, and turbulence model setting parameters; and simulating the air pressure on the armature using control equations based on the second boundary condition, the airflow field simulation model, and the turbulence model, where the control equations include any one or more of the mass conservation equation, momentum conservation equation, and energy conservation equation.

[0092] The step of extracting the airflow domain of the high-frequency solenoid valve based on its internal structure includes: determining the gas inlet, gas flow direction, and gas outlet based on the internal structure of the high-frequency solenoid valve; setting an external flow field based on the gas outlet; and extracting the airflow domain based on the gas inlet, the gas flow direction, and the external flow field.

[0093] Fluid-structure interaction was used to analyze the effect of airflow on armature motion and the pressure response characteristics of airflow.

[0094] The air pressure on the armature is calculated by integrating the air pressure on the upper and lower surfaces of the armature using the following formula:

[0095]

[0096] In the formula, represents the air pressure exerted on the armature; p represents the air pressure exerted on the upper and lower surfaces of the armature; Indicates the surface area of ​​the armature that bears the force; Represents the unit normal vector of the surface;

[0097] The k-ω turbulence model is used to simulate the airflow field inside the solenoid valve;

[0098] Using the arbitrary Lagrange-Euler method, the moving armature structure is defined as the airflow field boundary, and the dynamic changes of the airflow field during the armature movement are simulated using a dynamic mesh.

[0099] For the turbulence model, wall treatment is performed using wall functions, and wall conditions are set as slip boundary conditions.

[0100] Based on the second boundary condition, the airflow field simulation model, and the turbulence model, the air pressure on the armature is simulated through the control equation.

[0101] S3. Based on the magnetic field simulation model, the airflow field simulation model, and the electromagnetic force and air pressure on the armature, establish a electromagnetic valve coupling simulation model;

[0102] In step S3, based on the magnetic field simulation model, the airflow field simulation model, and the electromagnetic force and air pressure acting on the armature, a coupled simulation model of the solenoid valve is established to simulate the displacement response data of the armature and the valve orifice pressure response data of the high-frequency solenoid valve. This includes: establishing a dynamic model based on the electromagnetic force and air pressure acting on the armature; establishing the coupled simulation model of the solenoid valve based on the magnetic field simulation model, the airflow field simulation model, and the dynamic model; simulating the coupled simulation model of the solenoid valve using a dynamic mesh; and solving the coupled simulation model of the solenoid valve through transient analysis to simulate the displacement response data of the armature and the valve orifice pressure response data of the high-frequency solenoid valve.

[0103] Add a solid mechanics module to COMSOL, and use the electromagnetic force and air pressure obtained from the above magnetic field and airflow field simulations as inputs to the dynamic model to simulate the armature displacement. In the solid mechanics module, specify the axial displacement of the armature as 0-0.2mm to fix its range of motion. At the same time, transfer the displacement as a variable of the magnetic field and airflow field to the above physical fields to analyze the airflow response characteristics during the armature movement. Through COMSOL's built-in magnetic field model, turbulence model, solid mechanics model, fluid-structure interaction model, and magnetomechanical model, realize the parameter transfer between the various physical fields, and construct an electromagnetic valve coupled simulation model of the electromagnetic field, airflow field, and motion field.

[0104] The step of using a moving mesh to simulate the coupled simulation model of the solenoid valve includes: setting the fluid region in contact with the armature as the deformation domain of the moving mesh, and setting the boundary of the deformation domain as a fixed boundary to determine the moving mesh setting information; and using the moving mesh to simulate the coupled simulation model of the solenoid valve based on the moving mesh setting information.

[0105] The simulation of the solenoid valve coupling simulation model using a dynamic mesh further includes: obtaining the mesh quality parameters of the dynamic mesh during the simulation process; and re-meshing the mesh when the mesh quality parameters are less than the mesh quality threshold.

[0106] S4. Based on the electromagnetic valve coupling simulation model, simulate the displacement response data of the armature and the valve port pressure response data of the high-frequency electromagnetic valve to obtain the response time of the high-frequency electromagnetic valve and complete the airflow control simulation of the high-frequency electromagnetic valve.

[0107] The present invention also provides a system for implementing the high-frequency solenoid valve airflow control simulation method, the schematic diagram of which is shown below. Figure 4 As shown, it includes a magnetic field simulation model building module, an airflow field simulation model building module, an electromagnetic valve coupling simulation model building module, and an electromagnetic valve airflow control simulation module;

[0108] The magnetic field simulation model building module establishes a magnetic field simulation model based on the components of the high-frequency solenoid valve and uploads the data to the solenoid valve coupling simulation model building module.

[0109] The airflow field simulation model building module establishes an airflow field simulation model based on the internal structure of the high-frequency solenoid valve and uploads the data to the solenoid valve coupling simulation model building module.

[0110] The electromagnetic valve coupling simulation model building module establishes a electromagnetic valve coupling simulation model based on the received data, the magnetic field simulation model, the airflow field simulation model, and the electromagnetic force and air pressure on the armature, and uploads the data to the electromagnetic valve airflow control simulation module.

[0111] Based on the received data and the electromagnetic valve coupling simulation model, the solenoid valve airflow control simulation module simulates the displacement response data of the armature and the valve port pressure response data of the high-frequency solenoid valve to obtain the response time of the high-frequency solenoid valve and complete the high-frequency solenoid valve airflow control simulation.

[0112] The method of the present invention will be further described below with reference to an embodiment:

[0113] A magnetic field geometric model is established based on the dimensions and materials of the components of a high-frequency solenoid valve. The high-frequency solenoid valve in an intelligent ore sorting machine mainly consists of a coil, iron core, moving armature, and outer shell. Its electromagnetic characteristics are primarily affected by the materials of these components and their relative positions. Key components of the high-frequency solenoid valve are extracted, and a three-dimensional geometric model is established based on their actual dimensions. Since the magnetic circuit of the high-frequency solenoid valve is relatively closed, non-magnetic materials such as end caps and coil frames can be ignored. Only key components such as the iron core, coil, armature, and outer shell are modeled to simplify the calculation process and save computational resources. The coil is made of multi-turn copper wire, so it can be modeled as an equivalent coil loop. Simultaneously, a square air domain needs to be set outside the high-frequency solenoid valve as a magnetically insulating boundary to enclose the entire solenoid valve and ensure that the electromagnetic field calculation is not affected by external factors. As an example, the simplified magnetic field geometric model is as follows: Figure 5 As shown.

[0114] The materials of each component of the high-frequency solenoid valve are crucial to the electromagnetic field calculation. The solenoid valve coil is made of copper wire, and the material is set to copper; the material of the air domain surrounding the solenoid valve is set to air; a soft magnetic material, electrical pure iron (DT4), is added to the material library, and the armature, iron core, and outer shell are set to DT4; corresponding material characteristic parameters such as conductivity, relative permeability, and magnetization curve (BH curve) are set for the above materials. Some material parameters are shown in Table 1.

[0115] Table 1

[0116]

[0117] The magnetization curve is a material property of soft magnetic materials, representing the relationship between magnetic field strength H and magnetic induction intensity B, and indicating the magnetization performance of the material. DT4 is one of the commonly used soft magnetic materials in high-frequency solenoid valve electromagnets, characterized by high permeability, magnetic saturation, and low hysteresis loss. Its magnetization curve is shown below. Figure 6 As shown.

[0118] The magnetic field mathematical model and the magnetic field geometric model together constitute the magnetic field simulation model. After the magnetic field simulation model is established, the first boundary condition is set. A cube-shaped air domain is set outside the magnetic field simulation model as the computational domain to isolate the influence of the external magnetic field and at the same time make the magnetic field boundary condition meet the requirements of infinite far field. The magnetic field is excited by an external current through a coil. The excitation current curve of the transient magnetic field is the actual measured working current curve of the solenoid valve, where the peak current is 7.4 amps (A) and the holding current is 0.93 A. The coil cross-section is taken as the excitation input terminal, and the wire model is set as a uniform multi-turn coil with 810 turns. The current direction is set by the coil geometry.

[0119] After applying an excitation current to the magnetic field based on the first boundary condition, the simulation yields a magnetic field line distribution cloud map inside the solenoid valve, as shown below. Figure 7 As shown in the figure, the maximum magnetic flux density of the solenoid valve is mainly concentrated in the iron core and armature region. This is because a strong magnetic field is formed in the iron core after the coil is energized. As part of the magnetic circuit, the high permeability of the iron core causes the magnetic flux to be highly concentrated within it, resulting in a large magnetic flux density. The magnetic field is stronger near the air gap at the top of the armature, and the magnetic flux density gradually decreases downwards. The magnitude of the electromagnetic force on the armature depends on the magnitude of the magnetic flux density on the armature; the greater the magnetic flux density, the greater the electromagnetic force on the armature and the faster the response. The magnetic field lines exhibit a uniform curved distribution around the coil, indicating that a good closed magnetic circuit is formed between the iron core and the armature. The magnetic flux density decays rapidly in the air region far from the magnetic circuit, which conforms to the decay law of electromagnetic fields. When the solenoid valve is in the closed state, the response curve of the electromagnetic force on the armature under the action of the excitation current is shown in the figure. Figure 8As shown, after the coil is energized, the electromagnetic force continuously increases. When the electromagnetic force reaches its peak value, a small holding current is applied, at which point the electromagnetic force begins to gradually decrease. When a reverse shut-off current is applied to the coil, the electromagnetic force rapidly decreases to zero.

[0120] During the opening and closing of a high-frequency solenoid valve, the armature moves up and down within the airflow domain. The armature's motion is influenced by air pressure, and the gas flow characteristics are also affected by the armature's displacement, involving fluid-solid interaction, which is analyzed using fluid-structure interaction (FSI). The simulation analysis of the solenoid valve's airflow field mainly includes two parts. First, the influence of airflow on armature motion, i.e., the air pressure exerted by the airflow on the armature. During the solenoid valve's opening, the direction of the air pressure is opposite to the armature's displacement, hindering the opening; during the closing, the direction of the air pressure is the same as the armature's displacement, pushing the armature and facilitating the closing. Second, the pressure response characteristics of the airflow, i.e., the change in outlet pressure during the solenoid valve's opening and closing. The opening or closing of the solenoid valve is essentially the up-and-down movement of the armature. Due to the armature's movement, the airflow domain changes accordingly, and the air pressure at the solenoid valve's outlet also changes accordingly.

[0121] Among them, the aerodynamic force of the solenoid valve mainly acts on the surface of the moving components of the solenoid valve. When high-pressure gas flows through the narrow flow space near the armature, the flow direction and speed of the gas will change due to contact with the surface of the armature, resulting in a change in the flow rate of the gas, which in turn generates a force on the surface of the armature. However, since the armature is an axisymmetric component, the radial forces acting on the surface of the armature can cancel each other out. Therefore, when analyzing the aerodynamic force on the surface of the solenoid valve armature, it is only necessary to analyze the axial aerodynamic force.

[0122] The structure of a high-frequency solenoid valve is relatively complex, resulting in a complex internal airflow channel. Based on the internal structure of the high-frequency solenoid valve, the airflow domain inside the valve is extracted, such as... Figure 9 As shown, gas can flow into the solenoid valve through the two inlets, the through hole in the middle of the iron core and the outside of the armature. It then flows through the inner hole of the armature and the working air gap in the plane to the end cover area, and finally flows out from the outlet of the solenoid valve. A cylindrical external flow field is set at the valve port to simulate the jet effect of the airflow at the outlet of the solenoid valve, and the pressure change curve of the jet airflow during the opening and closing of the high-frequency solenoid valve is analyzed.

[0123] The simulation conditions were set, including the following steps: When the solenoid valve is open, high-pressure airflow passes through the solenoid valve and flows out from the outlet to purge the ore. The airflow inside the solenoid valve is in a high-speed flow state. Moreover, the internal structure of the solenoid valve is relatively complex, with local narrow areas. For example, the axial dimension at the armature working air gap is small, only 0.2 mm. When the gas flows through this area, the flow velocity increases rapidly, easily forming turbulence.

[0124] Using the Arbitrary Lagrangian-Eulerian Method (ALE), the moving armature structure is defined as the airflow field boundary, and a dynamic mesh is used to simulate the dynamic changes in the airflow field during armature movement. For the turbulence model, wall functions are selected for wall treatment, and the wall conditions are set to slip boundary conditions. The airflow domain has two inlets; inlet 1 and inlet 2 are both defined as pressure inlets, with the inlet pressure set to a static pressure of 0.7 MPa, and the flow direction is normal. The outer flow field surface is a free boundary, defined as a pressure outlet, with the outlet pressure set to 0 MPa.

[0125] Based on the pre-set second boundary conditions, airflow field simulation model, and turbulence model, the air pressure on the armature is simulated using control equations. The airflow pressure distribution cloud map when the solenoid valve is fully open is shown below. Figure 10 As shown, gas can flow into the solenoid valve through the internal through-holes of the iron core and the working air gap at the armature, so the air pressure in the upper region of the armature is maintained at 0.8 MPa; the gas pressure drop is mainly concentrated in the air gap below the armature and the valve port. When the gas flows through the narrow area below the armature, the air pressure decreases rapidly, creating a pressure difference between the upper and lower surfaces of the armature, generating air pressure acting on the armature; after passing through the air gap, the gas flows towards the end cap and finally is ejected from the valve port; after the airflow enters the air, the pressure begins to diffuse outwards, and as the airflow continues to move forward, the pressure gradually decreases to atmospheric pressure. Simulation results show that the air pressure on the armature is 53 N when the solenoid valve is closed and 12 N when it is fully open.

[0126] The high-frequency solenoid valve used in the intelligent ore sorting machine is a system in which multiple physical fields are coupled together, such as... Figure 11 As shown, there is an interaction between its magnetic field, flow field, and mechanical motion field. When an excitation current is passed through the electromagnetic coil, the magnetic field generates an electromagnetic force that acts on the armature, causing the armature to move. The displacement of the armature changes the valve opening, thereby affecting the flow field distribution in the airflow channel. At the same time, the airflow exerts a reaction force on the armature. Since the change in the armature displacement will change the magnetic field and airflow field, it will affect the magnitude of the electromagnetic force and air pressure, leading to a change in the motion state of the armature, thus forming a feedback.

[0127] Add a solid mechanics module to COMSOL, and use the electromagnetic force and air pressure obtained from the above magnetic field and airflow field simulations as inputs to the dynamic model to simulate the armature displacement. In the solid mechanics module, specify the axial displacement of the armature as 0-0.2mm to fix its range of motion. At the same time, transfer the displacement as a variable of the magnetic field and airflow field to the above physical fields to analyze the airflow response characteristics during the armature movement. Through COMSOL's built-in magnetic field model, turbulence model, solid mechanics model, fluid-structure interaction model, and magnetomechanical model, realize the parameter transfer between the various physical fields, and construct an electromagnetic valve coupled simulation model of the electromagnetic field, airflow field, and motion field.

[0128] To accurately simulate the motion of the armature and the changing characteristics of airflow during the opening and closing of a solenoid valve, a dynamic mesh module is introduced. Since the only moving component of the entire solenoid valve is the armature, the fluid region in contact with the armature is set as the deformation domain of the dynamic mesh. This allows the fluid domain to change with the movement of the armature, thereby transferring the armature displacement parameters to the electromagnetic and airflow fields. Simultaneously, because the inlet of the airflow domain coincides with the boundary of the deformation domain, the boundary of the deformation domain is set as a fixed boundary to improve model convergence, thus defining the dynamic mesh settings.

[0129] During the opening / closing of the solenoid valve, the armature moves up and down, causing the adjacent gas domain mesh to stretch or compress, which may degrade the mesh quality and affect the model's computational accuracy and convergence. Therefore, an automatic re-meshing function is introduced. Specific steps may include: setting a mesh quality threshold, acquiring the mesh quality parameters of the moving mesh during simulation, and automatically re-meshing the model when the mesh quality parameters are lower than the threshold to maintain a good mesh quality.

[0130] A coupled simulation model of the solenoid valve is solved through transient analysis to simulate the opening and closing process of the high-frequency solenoid valve. The displacement response curve of the armature and the pressure response curve of the valve orifice are output to analyze the dynamic response characteristics of the high-frequency solenoid valve during the switching process. This coupled simulation model of the solenoid valve can accurately reflect the dynamic movement process of the armature and the change process of airflow pressure at the valve orifice.

[0131] Figure 12 The diagram shows the curves of electromagnetic force and air pressure changing over time during the switching process of a high-frequency solenoid valve. When current is applied to the coil, the electromagnetic force gradually increases. When the electromagnetic force on the armature increases to a level greater than the air pressure, the armature begins to move, and the solenoid valve gradually opens. As the armature displacement increases, the working air gap gradually decreases, further strengthening the electromagnetic force under the same current. Therefore, the curve shows an inflection point during armature movement, with the rate of increase accelerating. Simultaneously, as the displacement increases and the working air gap decreases, the gap on the lower plane of the armature increases, reducing the air pressure drop and thus decreasing the pressure difference between the upper and lower surfaces of the armature, causing the air pressure to gradually decrease. Similarly, when a reverse closing current is applied to the coil, the electromagnetic force gradually decreases to a level less than the air pressure, and the armature, under the action of the air pressure, undergoes a restoring motion, causing the air pressure to gradually increase back to its initial value.

[0132] The displacement response curve of the armature under the combined action of electromagnetic force and air pressure is as follows: Figure 13 As shown; the valve port pressure response curve during the solenoid valve switching process is as follows: Figure 14As shown in the figure, the armature begins to move at 0.6 ms, reaches its maximum displacement at 0.82 ms, and the solenoid valve is fully open. When a closing signal is given to the solenoid valve at 1.2 ms, the electromagnetic force rapidly decreases, and the armature begins its return motion at 1.58 ms, returning to its original position at 1.82 ms, thus fully closing the solenoid valve. Simultaneously, the outlet air pressure of the solenoid valve reaches its maximum with a lag of 0.86 ms; after the solenoid valve closes, it returns to atmospheric pressure at 1.86 ms.

[0133] based on Figure 13 and Figure 14 As shown, the main function of the high-frequency solenoid valve is to control the on / off of high-pressure airflow to achieve the task of ore injection and separation. Therefore, the pressure response time is mainly used as the performance indicator of the high-frequency solenoid valve. The response time of the high-frequency solenoid valve is shown in Table 2. Within one switching cycle, the displacement response time is 1.44 ms and the pressure response time is 1.51 ms. The airflow response of the solenoid valve lags slightly behind the displacement change of the armature. Specifically, the airflow response lags by 0.86 ms when opening and by 0.65 ms when closing.

[0134] Table 2

[0135]

[0136] The technical solution provided by this invention not only accurately simulates the switching process of a high-frequency solenoid valve, but also considers the dynamic changes in airflow during the switching process, accurately simulating the response process of the air pressure injected at the valve orifice of the high-frequency solenoid valve. This improves the accuracy of analyzing the opening, closing, and response time of the high-frequency solenoid valve, thereby improving the airflow control precision of the high-frequency solenoid valve.

[0137] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A high frequency solenoid valve airflow control simulation method, characterized by, The method comprises the following steps: S1. Based on the components of the high-frequency electromagnetic valve, a magnetic field simulation model is established; S2. Based on the internal structure of the high-frequency electromagnetic valve, an airflow field simulation model is established; S3. Based on the magnetic field simulation model, the airflow field simulation model, and the electromagnetic force and air pressure force on the armature, an electromagnetic valve coupling simulation model is established; S4. Based on the electromagnetic valve coupling simulation model, the displacement response data of the armature and the valve port pressure response data of the high-frequency electromagnetic valve are simulated to obtain the response time of the high-frequency electromagnetic valve, and the high-frequency electromagnetic valve airflow control simulation is completed; Step S1 comprises the following steps: Based on Maxwell's equations, a magnetic field mathematical model is established; Based on the size and material of the components of the high-frequency electromagnetic valve, a magnetic field geometric model is established; Based on the magnetic field mathematical model and the magnetic field geometric model, a magnetic field simulation model is determined; A first boundary condition is set, the first boundary condition includes an excitation current curve; based on the excitation current curve, an excitation is applied to the magnetic field simulation model to simulate the electromagnetic force on the armature; The magnetic field mathematical model based on Maxwell's equations is specifically as follows: Based on Maxwell's electromagnetic valve theory, the differential form of Maxwell's equations is as follows: The auxiliary equations among the four field quantities in the above formula are as follows: where H represents magnetic field strength; J represents current density; D represents electric displacement vector; E represents electric field strength; B represents magnetic induction intensity; represents electric charge density; represents soft magnetic material permeability; represents dielectric constant; represents soft magnetic material conductivity; The vector magnetic potential A is introduced, and the following equation is obtained: After solving each field quantity by using the finite element method, the electromagnetic force on the armature is solved by using the Maxwell stress tensor method, and the formula of the magnetic field mathematical model is as follows: wherein represents the electromagnetic force on the armature; represents the magnetic permeability in vacuum ; S represents an arbitrary closed surface of the medium; n represents the unit normal vector on the closed surface.

2. The high-frequency electromagnetic valve airflow control simulation method according to claim 1, characterized by, Based on the size and material of the components of the high-frequency electromagnetic valve, the magnetic field geometric model is established, which includes: setting an air threshold as a magnetic insulation boundary outside the high-frequency electromagnetic valve; setting the material characteristic parameters of each component and the air threshold; modeling the components of the high-frequency electromagnetic valve and the air threshold based on the size of each component and the material characteristic parameters, and establishing the magnetic field geometric model.

3. The high frequency solenoid valve airflow control simulation method according to claim 1, characterized by, The magnetic field mathematical model and the magnetic field geometric model jointly constitute the magnetic field simulation model, and the first boundary condition is set after the magnetic field simulation model is established; the outside of the magnetic field simulation model is provided with a cubic air domain as a calculation domain to isolate the influence of external magnetic field and meet the requirement of infinite field boundary condition; the coil applies an excitation source to the magnetic field, and the excitation form is external current; After applying the excitation current to the magnetic field based on the first boundary condition, the internal magnetic field of the electromagnetic valve is simulated; the electromagnetic force on the armature is simulated.

4. The high frequency solenoid valve airflow control simulation method according to claim 1, characterized by, In step S2, based on the internal structure of the high-frequency electromagnetic valve, a gas flow field simulation model is established to simulate the gas pressure on the armature, including: based on the internal structure of the high-frequency electromagnetic valve, extracting the gas flow field of the high-frequency electromagnetic valve; based on the gas flow field of the high-frequency electromagnetic valve, establishing the gas flow field simulation model; using a turbulence model to simulate the gas flow field in the gas flow field simulation model; setting a second boundary condition, the second boundary condition includes any one or more of the inlet boundary parameter, the outlet boundary parameter and the turbulence model setting parameter; based on the second boundary condition, the gas flow field simulation model and the turbulence model, the gas pressure on the armature is simulated by a control equation, the control equation includes any one or more of the mass conservation equation, the momentum conservation equation and the energy conservation equation.

5. The high frequency solenoid valve airflow control simulation method according to claim 4, characterized by, Based on the internal structure of the high-frequency electromagnetic valve, the gas flow field of the high-frequency electromagnetic valve is extracted, including: based on the internal structure of the high-frequency electromagnetic valve, determining the gas inlet, the gas flow direction and the gas outlet; based on the gas outlet, setting the outflow field; based on the gas inlet, the gas flow direction and the outflow field, extracting the gas flow field; Fluid-structure interaction is used to analyze the influence of gas flow on the movement of the armature and the pressure response characteristics of the gas flow; The gas pressure on the armature is calculated by integrating the gas flow pressure on the upper and lower surfaces of the armature, and the following formula is used to calculate: In the formula, represents the air pressure force on the armature; p represents the air pressure on the upper and lower surfaces of the armature; represents the force area on the surface of the armature; represents the unit normal vector of the surface; The k-ω turbulence model is used to simulate the internal gas flow field of the electromagnetic valve; By arbitrary Lagrangian-Eulerian method, the moving armature structure is defined as the boundary of the gas flow field, and the dynamic mesh is used to simulate the dynamic change of the gas flow field when the armature moves; The wall treatment of the turbulence model selects the wall function, and the wall condition is set as the slip boundary condition; Based on the second boundary condition, the gas flow field simulation model and the turbulence model, the gas pressure on the armature is simulated by a control equation.

6. The high frequency solenoid valve airflow control simulation method according to claim 1, characterized by, In step S3, based on the magnetic field simulation model, the gas flow field simulation model and the electromagnetic force and gas pressure on the armature, an electromagnetic valve coupling simulation model is established to simulate the displacement response data of the armature and the valve port pressure response data of the high-frequency electromagnetic valve, including: based on the electromagnetic force and gas pressure on the armature, a dynamics model is established; based on the magnetic field simulation model, the gas flow field simulation model and the dynamics model, the electromagnetic valve coupling simulation model is established; the electromagnetic valve coupling simulation model is simulated by using dynamic mesh; the electromagnetic valve coupling simulation model is solved by transient analysis to simulate the displacement response data of the armature and the valve port pressure response data of the high-frequency electromagnetic valve.

7. The high frequency solenoid valve airflow control simulation method according to claim 6, characterized by, In comsol, add the solid mechanics module, the magnetic field, the airflow field simulation electromagnetic force, air pressure as the input of the dynamics model, simulation obtained armature displacement; in the solid mechanics module, specify the armature axial movement displacement is 0-0.2mm, fix its movement range; at the same time, the displacement is as the variable of the magnetic field, airflow field is passed to the magnetic field simulation model and airflow field simulation model, analyze the response characteristics of the airflow in the movement process of the armature; through the magnetic field model, turbulence model, solid mechanics model, fluid-solid coupling model and magnetomechanics model of comsol, realize the parameter mutual transmission between each physical field, build the electromagnetic valve coupling simulation model of electromagnetic field, airflow field and movement field; The simulation of the electromagnetic valve coupling simulation model by using the dynamic grid comprises: setting the fluid region in contact with the armature as a deformation domain of the dynamic grid, setting the boundary of the deformation domain as a fixed boundary, and determining the dynamic grid setting information; based on the dynamic grid setting information, the electromagnetic valve coupling simulation model is simulated by using the dynamic grid; The simulation of the electromagnetic valve coupling simulation model by using the dynamic grid further comprises: obtaining the grid quality parameter of the dynamic grid during the simulation; when the grid quality parameter is less than the grid quality threshold, the grid is redivided.

8. A system for implementing the method of claim 1 to 7, characterized in that, The simulation of the electromagnetic valve coupling simulation model by using the dynamic grid further comprises: obtaining the grid quality parameter of the dynamic grid during the simulation; when the grid quality parameter is less than the grid quality threshold, the grid is redivided. The simulation of the electromagnetic valve coupling simulation model by using the dynamic grid further comprises: obtaining the grid quality parameter of the dynamic grid during the simulation; when the grid quality parameter is less than the grid quality threshold, the grid is redivided. The simulation of the electromagnetic valve coupling simulation model by using the dynamic grid further comprises: obtaining the grid quality parameter of the dynamic grid during the simulation; when the grid quality parameter is less than the grid quality threshold, the grid is redivided. The simulation of the electromagnetic valve coupling simulation model by using the dynamic grid further comprises: obtaining the grid quality parameter of the dynamic grid during the simulation; when the grid quality parameter is less than the grid quality threshold, the grid is redivided. The simulation of the electromagnetic valve coupling simulation model by using the dynamic grid further comprises: obtaining the grid quality parameter of the dynamic grid during the simulation; when the grid quality parameter is less than the grid quality threshold, the grid is redivided.

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